[volt-nuts] 3458A question

[Poul-Henning Kamp]

--------
In message <003801d389fb$bbba1f10$332e5d30$@perdrix.co.uk>, "David C. Partridge
" writes:

>After running an ACAL 0 with a four wire short in place I get a DCV reading
>starting at about  -0.00005 mV to increasing to about 0.00060 to 0.00070 mV
>over a minute or so at which point it seems to stabilise.

That is pretty normal, it's very hard to control temperatures so precisely
that you don't get a few hundred nanovolts of seebeck voltage.

If you touch the short with your finger, you will change the temperature
enough that it registers clearly.

I mount the short, then hang a piece of cloth over the terminals and wait
about 15-30 minutes before I run ACAL 0



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